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131.
本文根据光纤光栅多传感器复用时信号的光谱特征,提出了采用成象光谱技术对复用信号进行解调的方案.文章推导分析了该复用方案的有关参量及特性,并进行了验证实验,获得了与计算结果吻合的实验结果. 相似文献
132.
分布光纤喇曼光子传感器系统的一种解调方法 总被引:11,自引:1,他引:10
本文提出一种新的解调方法,在DOFRPS(分布光纤喇曼光子传感器)系统中采用Rayleigh散射OTDR(光学时域反射)曲线解调Raman散射OTDR曲线,提高了系统的测温灵敏度、测温精度,扩展了系统的功能,在2km光纤上可实时测量1000个点的温度、应力和压力;在系统中设置了光纤取样环,确定系统的修正系数,通过计算机进行实时修正,提高了测量稳定性,实验结果与理论分析一致,系统的测温精度达±1℃。 相似文献
133.
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135.
A linear sweep adsorptive stripping voltammetric method for the determination of netilmicin in the presence of formaldehyde
has been proposed for the first time. In the presence of 3.0×10−3 g ml−1 formaldehyde, netilmicin exhibits a sensitive cathodic peak at −1.30 V (vs. the saturated calomel electrode, SCE) in a medium
of Britton–Robinson buffer (pH 8.7) with a scan rate of 100 mV s−1 after a preconcentration period of 120 s at −1.10 V (vs. SCE). The peak current showed a linear dependence on the netilmicin
concentration over the range 4.2×10−9–1.0×10−7 g ml−1. The achieved limits of detection and quantitation were 1.0×10−10 and 3.3×10−10 g ml−1 netilmicin, respectively. It was deduced from the experiments that the amine–aldehyde condensation product formed between
netilmicin and formaldehyde is mainly responsible for the appearance of the peak. The electrochemical behavior of netilmicin
in the presence of formaldehyde has been studied. The method was applied to the direct determination of netilmicin in injectable
formulations and spiked human urine and serum samples.
相似文献
136.
In the presence of DMSO as co-solvent and under vigorous agitation, baker's yeast in water was found to reduce substituted fluorenones to the corresponding fluorenols in good to excellent enantioselectivities. 相似文献
137.
Morita K Sankaran NB Huang W Seino T Sato Y Nishizawa S Teramae N 《Chemical communications (Cambridge, England)》2006,(22):2376-2378
An abasic site-containing DNA combined with lumiflavin allows amperometric determination of single nucleotide polymorphism through hydrogen bond-mediated nucleobase recognition in water by using abasic sites as a molecular recognition field. 相似文献
138.
[STRUCTURE: SEE TEXT] The ansamycin antibiotics contain metacyclophanic macrolactams, many of which possess potent antitumor activity. Only a few total syntheses of this family of natural products have been reported, and modifications to increase potency have not been described. Therefore, a method was developed to prepare the trienomycin A core via resin-bound triphenylphosphonium salts, which serve as both a reagent and a traceless linker to afford olefinic products that undergo ring-closing metathesis (RCM) to give macrocyclic scaffolds of varying ring sizes. 相似文献
139.
New fuzzy models for time-cost trade-off problem 总被引:1,自引:0,他引:1
The time-cost trade-off problem is a specific type of the project scheduling problem which studies how to modify project activities
so as to achieve the trade-off between the completion time and the project cost. In real projects, the trade-off between the
project cost and the completion time, and the uncertainty of the environment are both considerable aspects for managers. In
this paper, three new fuzzy time-cost trade-off models are proposed, in which credibility theory is applied to describe the
uncertainty of activity duration times. A searching method by integrating fuzzy simulation and genetic algorithm is produced
to search the quasi-optimal schedules under some decision-making criteria. The purpose of the paper is to reveal how to obtain
the optimal balance of the completion time and the project cost in fuzzy environments. 相似文献
140.
针对重离子加速器部分电源的控制要求,进行了分析研究,提出并实现了一种实时、高效、多功能的控制系统。该系统基于数字信号处理器(DSP)和两片现场可编程门阵列(FPGA)芯片相结合的核心处理构架,在系统后端利用PXI总线接口配合FPGA来与工控机箱中的系统控制器和其他控制组件进行大批量数据交互;系统前端利用直接数字频率合成器、模数转换器和数模转换器等器件结合DSP和FPGA中的控制算法及相应控制机制来实现对不同电源控制参数的处理和功率的输出;平台中两组光纤模块也与FPGA相配合实现对同步触发事例等实时数据的收发和调试。 相似文献